Othnielia rex , skeletal reconstruction
|Upper Jurassic (early Tithonian )|
|152.1 to 147.7 million years|
|Galton , 1977|
Othnielia is a genus of bird basin dinosaurs (Ornithischia), the validity of which is disputed. This genus is based on a thigh bone with a few other, postcranial remains ( holotype , copy number YPM 1875), which comes from the late Upper Jurassic North America.
In the past, other finds, including two fragmentary skeletons and skull material, were ascribed to this genus. However, a revision of the genus by Peter Galton (2007) showed that the holotype material did not show any diagnostic features that would, however, be necessary to distinguish the genus. An assignment of further finds to Othnielia is therefore lacking. Galton therefore established a new genus for the other finds once attributed to Othnielia , Othnielosaurus , and considered the genus Othnielia as a noun dubium (dubious name).
Research history and naming
BF Mudge discovered the holotype material from the layers of the Morrison Formation near Garden Park near Cañon City in the US state of Colorado . In 1877 the find was scientifically described for the first time by Othniel Charles Marsh as a new species of the genus Nanosaurus ( Nanosaurus rex ) . Marsh described the animal as a "small, fox-sized dinosaur". Galton and Jensen (1973) recognized similarities with the genus Hypsilophodon and ascribed Nanosaurus to the Hypsilophodontidae , a family that is now considered paraphyletic and is therefore no longer used.
Galton (1977) recognized important differences between Nanosaurus rex and the type species of Nanosaurus , and put Nanosaurus rex therefore in its own genus, which he othnielia called ( othnielia rex ). The name Othnielia honors the eminent paleontologist Othniel Charles Marsh.
- Gregory S. Paul : The Princeton Field Guide To Dinosaurs. Princeton University Press, Princeton NJ et al. 2010, ISBN 978-0-691-13720-9 , p. 275, online .
- Peter M. Galton , Teeth of ornithischian dinosaurs (mostly Ornithopoda) from the Morrison Formation (Upper Jurassic) of the western United States. In: Kenneth Carpenter (Ed.): Horns and Beaks. Ceratopsian and Ornithopod Dinosaurs. Indiana University Press, Bloomington IN 2007, ISBN 978-0-253-34817-3 , pp. 17-47.
- Othniel C. Marsh : Notice of new dinosaurian reptiles from the Jurassic formations. In: American Journal of Science and Arts. Series 3, Vol. 14 = Vol. 114, No. 84, Article 53, 1877, , pp. 514-516, digitized .
- David B. Norman , Hans-Dieter Sues , Lawrence M. Witmer , Rodolfo A. Coria : Basal Ornithopoda. In: David B. Weishampel , Peter Dodson , Halszka Osmólska (eds.): The Dinosauria . 2nd edition. University of California Press, Berkeley CA et al. 2004, ISBN 0-520-24209-2 , pp. 393-412, digitized version (PDF; 2.66 MB) .
- Donald F. Glut : Dinosaurs. The encyclopedia. McFarland & Company, Jefferson NC et al. 1997, ISBN 0-89950-917-7 .
- Peter M. Galton: The ornithopod dinosaur Dryosaurus and a Laurasia-Gondwanaland connection in the Upper Jurassic. In: Nature . Vol. 268, No. 5617, 1977, pp. 230-232, doi : 10.1038 / 268230a0 .